Apparatus for driving shuttle of embroidery machine

ABSTRACT

Disclosed is an apparatus for driving a shuttle of an embroidery machine. The apparatus comprises: a rotation shaft of the shuttle; a lower shaft which transfers a driving power to the rotation shaft, so as to rotate the shuttle; a first magnet provided at the rotation shaft; and a second magnet provided at the lower shaft and corresponding to the first magnet. The first magnet has a hollow cylindrical shape so that the rotation shaft can be inserted through the first magnet while firmly holding the first magnet. The second magnet has a hollow cylindrical shape so that the lower shaft can be inserted through the second magnet while firmly holding the second magnet.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an apparatus for driving a shuttle of an embroidery machine, and more particularly, to an apparatus for driving a shuttle, in which power for driving the shuttle is transferred in a non-contact manner using a magnetic force, so that the apparatus can be used permanently and generates reduced noise.

[0003] 2. Description of the Prior Art

[0004] As generally known in the art, an embroidery machine comprises a needle bar which moves up and down and a shuttle which makes stitches in cooperation with the needle bar. Hereinafter, a general apparatus for driving a shuttle, which is employed in a conventional embroidery machine, will be described.

[0005]FIG. 1 is an external view of a conventional embroidery machine. The conventional embroidery machine includes a rectangular table (not shown) and an embroidery frame (not shown) placed on the table to hold a workpiece fabric to be embroidered. A plurality of heads 1, each of which has a plurality of sewing needles, are mounted on the embroidery frame and a plurality of shuttle assemblies 2 are mounted below the table. Each of the shuttle assemblies 2 includes a shuttle 2 a (see FIG. 2), which is opposed to the heads 1 and supplies a shuttle thread.

[0006] Further, the embroidery machine includes an upper shaft 3 extending through the heads 1 aligned in a row, a lower shaft 4 extending through the shuttle assemblies 2 aligned in a row, and a rotational force transfer mechanism 5 connected to the upper shaft 3 and the lower shaft 4 so as to transfer the rotational force of a spindle drive motor 6 to the upper shaft 3 and the lower shaft 4.

[0007]FIG. 2 is a view showing an interior of a shuttle driving apparatus employed in the conventional embroidery machine, and FIG. 3 is a perspective view of the shuttle driving apparatus employed in the conventional embroidery machine. As shown, the conventional apparatus for driving a shuttle includes a following bevel gear 2 c and a driving bevel gear 4 a. The following bevel gear 2 c is fixed to a rear end of a rotation shaft 2 b of the shuttle 2 a. The driving bevel gear 4 a is fixed to the lower shaft 4 and engaged with the following bevel gear 2 c.

[0008] Hereinafter, the operation of the conventional embroidery machine having the above-mentioned construction will be described.

[0009] First, when a user inputs operation data to an operating unit (not shown) in order to embroider a workpiece fabric with various patterns, a control unit (not shown) issues commands to X- and Y-axis driving motors and the spindle drive motor 6.

[0010] Then, according to the commands issued from the control unit, the X- and Y-axis driving motors move the embroidery frame in X- and Y-axis directions, and the spindle drive motor 6 moves the upper shaft 3 and the lower shaft 4 by means of the rotational force transfer mechanism 5.

[0011] Then, the upper shaft 3 operates the heads 1 and the lower shaft 4 rotates the shuttle 2 a of the shuttle assembly 2, so as to form stitches by the cooperation of the head 1 and the shuttle assembly 2.

[0012] In this case, a construction for rotating the shuttle 2 a of the shuttle assembly 2 can be understood by FIGS. 2 and 3. As shown, when the lower shaft 4 rotates, the driving bevel gear 4 a provided at the lower shaft 4 rotates together with the following bevel gear 2 c engaged with the driving bevel gear 4 a. This rotation of the following bevel gear 2 c causes the shuttle 2 a to rotate.

[0013] However, since the conventional apparatus for driving a shuttle has a gear construction as described above, it is indispensable to periodically inject grease (mineral oil containing lithium) into a gap between the driving bevel gear 4 a of the lower shaft 4 and the following bevel gear 2 c of the shuttle 2 a, which causes inconvenience.

[0014] Further, the gear-type power transmission as described above causes the driving bevel gear 4 a and the following bevel gear 2 c to be worn, thereby shortening their lifespan.

[0015] Moreover, since the rotation shaft 2 b of the shuttle 2 a is engaged with the lower shaft 4 in a geared manner, when an overload is applied to the shuttle 2 a from the lower shaft 4, the shuttle 2 a may be forcedly rotated, and even, may be broken.

[0016] In addition, the gear engagement between the members generates mechanical noise during their rotation, which deteriorates the working environment.

SUMMARY OF THE INVENTION

[0017] Accordingly, the present invention has been made to solve the above-mentioned problems occurred in the prior art, and an object of the present invention is to provide an apparatus for driving a shuttle of an embroidery machine, which can rotate the shuttle in a non-contact manner using a magnetic force, thereby eliminating the inconvenience of periodically injecting grease into a gap between gears in the conventional embroidery machine.

[0018] It is another object of the present invention to provide an apparatus for driving a shuttle of an embroidery machine, which generates no mechanical abrasion, so that the apparatus can be used permanently.

[0019] It is still another object of the present invention to provide an apparatus for driving a shuttle of an embroidery machine, in which rotational force is transferred in a non-contact manner, so as to prevent mechanical vibration and noise from being generated.

[0020] It is another object of the present invention to provide an apparatus for driving a shuttle of an embroidery machine, in which the shuttle is driven by a magnetic force, so that a rotation shaft of the shuttle can rotates without contacting a lower shaft of the embroidery machine, thereby preventing the shuttle from being broken even when a load above a proper level is applied to the shuttle.

[0021] It is another object of the present invention to provide an apparatus for driving a shuttle of an embroidery machine, which can be easily maintained and can remarkably prolong a cycle of managing the shuttle.

[0022] To achieve the above and other objects of the present invention, there is provided an apparatus for driving a shuttle of an embroidery machine, the apparatus comprising: a rotation shaft of the shuttle; a lower shaft which transfers a driving power to the rotation shaft, so as to rotate the shuttle; a first magnet provided at the rotation shaft; and a second magnet provided at the lower shaft and corresponding to the first magnet.

[0023] It is preferred that the first magnet has a hollow cylindrical shape so that the rotation shaft can be inserted through the first magnet while firmly holding the first magnet and the second magnet has a hollow cylindrical shape so that the lower shaft can be inserted through the second magnet while firmly holding the second magnet.

[0024] It is also preferred that the first magnet and the second magnet are disposed in directions intersecting each other and each of the first magnet and the second magnet has a plurality of polar sections, each of which has an individual polarity. More preferably, the polar sections may be disposed in such a manner that polarities of the polar sections alternate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0026]FIG. 1 is a front view of a conventional embroidery machine;

[0027]FIG. 2 is a front view showing an interior of a shuttle driving apparatus employed in the conventional embroidery machine;

[0028]FIG. 3 is a perspective view of the shuttle driving apparatus employed in the conventional embroidery machine;

[0029]FIG. 4 is a front view of an apparatus for driving a shuttle of an embroidery machine according to the present invention;

[0030]FIG. 5 is a perspective view of an apparatus for driving a shuttle of an embroidery machine according to the present invention, in which the first magnet and the second magnet intersect each other at a right angle; and

[0031]FIG. 6 is a view showing a state in which a magnetic force is exerted between polar sections of the first and second magnets shown in FIG. 5.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

[0033]FIG. 4 is a front view of an apparatus for driving a shuttle of an embroidery machine according to the present invention. The apparatus includes a rotation shaft 22 for a shuttle 21 and a lower shaft 40 which transfers a driving power to the rotation shaft 22 in order to rotate the shuttle 21. A first magnet 23 is provided at the rotation shaft 22, and a second magnet 41 corresponding to the first magnet 23 is provided at the lower shaft 40. That is, the lower shaft 40 and the rotation shaft 22 extend in directions intersecting each other, the second magnet 41 is located at a portion of the lower shaft 40, which overlaps the rotation shaft 22 of the shuttle 21, and the first magnet 23 is located at a portion of the rotation shaft 22, which overlaps and is adjacent to the second magnet 41.

[0034] The first magnet 23 has a hollow cylindrical shape so that the rotation shaft 22 can be inserted through the first magnet 23 while firmly holding the first magnet 23, and the second magnet 41 has a hollow cylindrical shape so that the lower shaft 40 can be inserted through the second magnet 41 while firmly holding the second magnet 41.

[0035]FIG. 5 is a perspective view of an apparatus for driving a shuttle of an embroidery machine according to the present invention, in which the first magnet 23 and the second magnet 41 intersect each other at a right angle.

[0036] As shown in FIG. 6, each of the first magnet 23 and the second magnet 41 includes a plurality of polar sections 23 a and 41 a. Each of the polar sections 23 a and 41 a has a spiral shape and an individual polarity. The polar sections 23 a and 41 a are arranged in such a manner that adjacent polar sections have polarities different from each other, for example, the polarities of the polar sections 23 a and 41 a may alternate in such a way as N-S-N.

[0037] Further, since the polar sections 23 a of the first magnet 23 are spaced a predetermined gap apart from the polar sections 41 a of the second magnet 41 while they intersect each other, a magnetic force is always exerted between the first magnet 23 and the second magnet 41.

[0038] Hereinafter, the operation of the shuttle driving apparatus according to the present invention, as constructed above, will be described.

[0039] First, when the lower shaft 40 provided at the shuttle assembly 20 rotates, the second magnet 41 provided at the lower shaft 40 also rotates. In this case, since the polar sections 23 a of the first magnet 23 and the polar sections 41 a of the lower shaft 40 have an alternating polarity construction in which N poles and S poles are alternately disposed, the first magnet 23 and the second magnet 41 repulse each other when polar sections having the same poles are opposed to each other and attract each other when polar sections having different poles are opposed to each other.

[0040] Therefore, the rotation shaft 22 of the shuttle 21 rotates following the rotation of the lower shaft 40 due to the magnetic property of the polar sections 23 a and 41 a in which repulsion exerts between the polar sections having the same polarities and attraction exerts between the polar sections having different polarities.

[0041] In other words, the magnetic force between the first magnet 23 and the second magnet 41 transfers the rotational force of the lower shaft 40 to the shuttle 21, thereby rotating the shuttle 21.

[0042] As described above, the shuttle 21 is not in contact with the lower shaft 40 and is rotated by the magnetic force transferring the rotational force of the lower shaft 40. Therefore, even when overload or excessive force is applied from the lower shaft 40, not all of but only a certain degree of the excessive force is transferred to the rotation shaft 22, thereby preventing the shuttle 21 from being broken.

[0043] AS described above, the present invention provides an apparatus for driving a shuttle of an embroidery machine, which can rotate the shuttle in a non-contact manner using a magnetic force, thereby eliminating the inconvenience of periodically injecting grease into a gap between gears in the conventional embroidery machine.

[0044] Further, the present invention provides an apparatus for driving a shuttle of an embroidery machine, which generates no mechanical abrasion, so that the apparatus has an extended lifespan, and even, can be used nearly permanently.

[0045] Moreover, in the apparatus, the rotational force is transferred in a non-contact manner, so as to prevent mechanical vibration and noise from being generated.

[0046] Furthermore, since the shuttle is driven by a magnetic force, the rotation shaft of the shuttle can rotates without contacting the lower shaft of the embroidery machine, thereby preventing the shuttle from being broken even when a load above a proper level is applied to the shuttle.

[0047] In addition, the present invention provides an apparatus for driving a shuttle of an embroidery machine, which can be easily maintained and can remarkably prolong a cycle of managing the shuttle.

[0048] Although a preferred embodiment of the present invention has been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. 

What is claimed is:
 1. An apparatus for driving a shuttle of an embroidery machine, the apparatus comprising: a rotation shaft of the shuttle; a lower shaft which transfers a driving power to the rotation shaft, so as to rotate the shuttle; a first magnet provided at the rotation shaft; and a second magnet provided at the lower shaft and corresponding to the first magnet.
 2. An apparatus for driving a shuttle of an embroidery machine as claimed in claim 1, wherein the first magnet has a hollow cylindrical shape so that the rotation shaft can be inserted through the first magnet while firmly holding the first magnet, and the second magnet has a hollow cylindrical shape so that the lower shaft can be inserted through the second magnet while firmly holding the second magnet.
 3. An apparatus for driving a shuttle of an embroidery machine as claimed in claim 1, wherein the first magnet and the second magnet are disposed in directions intersecting each other, and each of the first magnet and the second magnet has a plurality of polar sections, each of which has an individual polarity.
 4. An apparatus for driving a shuttle of an embroidery machine as claimed in claim 3, wherein the polar sections are disposed in such a manner that polarities of the polar sections alternate. 